Clinical and laboratory test in patients with familial amyloid polyneuropathy (TTR-FAP): differences between symptomatic patients and asymptomatic carriers

Introducción: La polineuropatía amiloidótica familiar asociada a transtirretina (PAF-TTR) es una enfermedad causada por el depósito el depósito de amiloide en los tejidos, cuya proteína precursora es la transtirretina. La afectación clínica y las alteraciones analíticas dependen del estadio y del momento del diagnóstico de la enfermedad. Métodos: Estudio transversal, observacional donde se recogieron datos clínicos y analíticos de 10 pacientes sintomáticos y 10 portadores asintomáticos. Resultados: De un total de 20 casos: 14 mujeres (70%) con una mediana de edad de 47.5 años. Todos los portadores asintomáticos se diagnosticaron por cribado familiar y el 90% de los pacientes sintomáticos tenían déficit sensitivo al diagnóstico con electromiograma (EMG) patológico (p=0,016). Los pacientes sintomáticos tenían mayor variabilidad de presión arterial, sistólica (p=0,016), diastólica (p=0,045) y de frecuencia cardíaca (p<0,005). En las alteraciones analíticas destacan un descenso de T4 libre (p<0,005) y la elevación de cistatina C (p=0,046) en los pacientes sintomáticos. En cuanto a la comparación por edades en 9 (45%) casos se realizó un diagnóstico tardío (≥50 años) y en 11 (55%) diagnóstico precoz (<50 años), la edad media era de 38,55 vs 61,56 años (p<0,005). Los diagnosticados de forma tardía tenían proteínas totales bajas (p=0,008), elevación de BUN sérica (p<0,005) y cistatina C (p=0,04). Conclusiones: Los pacientes sintomáticos fueron diagnosticados por la presencia de síntomas neurológicos y disfunción autonómica. En cuanto a la comparación entre la edad al diagnóstico, los casos con diagnóstico precoz presentaban mayor implicación familiar, menor número de órganos afectados, escasa sintomatología neurológica y manifestaciones más leves.Background: Transthyretin-associated Familial Amyloid Polyneuropathy (TTR-PAF) is a disease caused by the deposit of abnormal transthyretin on the tissues, mainly on the nerves. The clinical affectation and laboratory test alterations depend on the clinical stage and the moment of disease diagnosis. Methods: A cross-sectional, observational study was performed. Medical records and laboratory test information of 20 patients: 10 symptomatic patients and 10 asymptomatic carriers. Results: Out of a total of 20 patients: 14 women (70 %) with a median age of 47.5 years. All of asymptomatic carriers were diagnosed for family history and 90 % of the symptomatic patients had neurologic impairment demonstrated with pathological electroneurography (NC) (p=0.016). The symptomatic patients had higher variability of blood pressure both systolic (p=0.016) and diastolic (p=0.045) and of heart rate (p<0.005). Regarding laboratory test alterations this patients presented a decrease of free T4 (p<0.005) and an increase of cystatine C (p=0.046). As for the comparison by age-at-onset in 9 (45 %) cases the diagnosis was late-onset (≥50 years) and 11 (55 %) early-onset (<50 years). Mean age was 38.55 vs 61.56 years (p<0.005). The late-onset group had a decrease of total proteins (p=0.008) and an increase of BUN (p<0.005) and cystatine C (p=0.04). Conclusions: Symptomatic patients were diagnosed by the presence of neurologic symptoms and vegetative symptoms. As to the comparison of age-at-onset, the early-onset has greater family history, minor number of affected organs, low neurological involvement and mild symptoms

Variabilidad clínica y analítica en casos con polineuropatía amioloidótica familiar (PAF-TTR): comparación entre portadores sanos y pacientes sintomáticos

Background: Transthyretin-associated Familial Amyloid Polyneuropathy (TTR-PAF) is a disease caused by the deposit of abnormal transthyretin on the tissues, mainly on the nerves. The clinical affectation and laboratory test alterations depend on the clinical stage and the moment of disease diagnosis. Methods: A cross-sectional, observational study was performed. Medical records and laboratory test information of 20 patients: 10 symptomatic patients and 10 asymptomatic carriers. Results: Out of a total of 20 patients: 14 women (70 %) with a median age of 47.5 years. All of asymptomatic carriers were diagnosed for family history and 90 % of the symptomatic patients had neurologic impairment demonstrated with pathological electroneurography (NC) (p=0.016). The symptomatic patients had higher variability of blood pressure both systolic (p=0.016) and diastolic (p=0.045) and of heart rate (p<0.005). Regarding laboratory test alterations this patients presented a decrease of free T4 (p<0.005) and an increase of cystatine C (p=0.046). As for the comparison by age-at-onset in 9 (45 %) cases the diagnosis was late-onset (≥50 years) and 11 (55 %) early-onset (<50 years). Mean age was 38.55 vs 61.56 years (p<0.005). The late-onset group had a decrease of total proteins (p=0.008) and an increase of BUN (p<0.005) and cystatine C (p=0.04). Conclusions: Symptomatic patients were diagnosed by the presence of neurologic symptoms and vegetative symptoms. As to the comparison of age-at-onset, the early-onset has greater family history, minor number of affected organs, low neurological involvement and mild symptoms.Introducción: La polineuropatía amiloidótica familiar asociada a transtirretina (PAF-TTR) es una enfermedad causada por el depósito el depósito de amiloide en los tejidos, cuya proteína precursora es la transtirretina. La afectación clínica y las alteraciones analíticas dependen del estadio y del momento del diagnóstico de la enfermedad. Métodos: Estudio transversal, observacional donde se recogieron datos clínicos y analíticos de 10 pacientes sintomáticos y 10 portadores asintomáticos. Resultados: De un total de 20 casos: 14 mujeres (70%) con una mediana de edad de 47.5 años. Todos los portadores asintomáticos se diagnosticaron por cribado familiar y el 90% de los pacientes sintomáticos tenían déficit sensitivo al diagnóstico con electromiograma (EMG) patológico (p=0,016). Los pacientes sintomáticos tenían mayor variabilidad de presión arterial, sistólica (p=0,016), diastólica (p=0,045) y de frecuencia cardíaca (p<0,005). En las alteraciones analíticas destacan un descenso de T4 libre (p<0,005) y la elevación de cistatina C (p=0,046) en los pacientes sintomáticos. En cuanto a la comparación por edades en 9 (45%) casos se realizó un diagnóstico tardío (≥50 años) y en 11 (55%) diagnóstico precoz (<50 años), la edad media era de 38,55 vs 61,56 años (p<0,005). Los diagnosticados de forma tardía tenían proteínas totales bajas (p=0,008), elevación de BUN sérica (p<0,005) y cistatina C (p=0,04). Conclusiones: Los pacientes sintomáticos fueron diagnosticados por la presencia de síntomas neurológicos y disfunción autonómica. En cuanto a la comparación entre la edad al diagnóstico, los casos con diagnóstico precoz presentaban mayor implicación familiar, menor número de órganos afectados, escasa sintomatología neurológica y manifestaciones más leves

Impact of genotype and phenotype on cardiac biomarkers in patients with transthyretin amyloidosis - Report from the Transthyretin Amyloidosis Outcome Survey (THAOS)

Aim: Cardiac troponins and natriuretic peptides are established for risk stratification in light-chain amyloidosis. Data on cardiac biomarkers in transthyretin amyloidosis (ATTR) are lacking. Methods and results: Patients (n = 1617) with any of the following cardiac biomarkers, BNP (n = 1079), NT-proBNP (n = 550), troponin T (n = 274), and troponin I (n = 108), available at baseline in the Transthyretin Amyloidosis Outcomes Survey (THAOS) were analyzed for differences between genotypes and phenotypes and their association with survival. Median level of BNP was 68.0 pg/ mL (IQR 30.5-194.9), NT-proBNP 337.9 pg/mL (IQR 73.0-2584.0), troponin T 0.03 μg/L (IQR 0.01-0.05), and troponin I 0.08 μg/L (IQR 0.04-0.13). NT-proBNP and BNP were higher in wild-type than mutant-type ATTR, troponin T and I did not differ, respectively. Non-Val30- Met patients had higher BNP, NT-proBNP and troponin T levels than Val30Met patients, but not troponin I. Late-onset Val30Met was associated with higher levels of troponin I and troponin T compared with early-onset. 115 patients died during a median follow-up of 1.2 years. Mortality increased with increasing quartiles (BNP/NT-proBNP Q1 = 1.7%, Q2 = 5.2%, Q3 = 21.7%, Q4 = 71.3%; troponin T/I Q1 = 6.5%, Q2 = 14.5%, Q3 = 33.9%, Q4 = 45.2%). Threeyear overall-survival estimates for BNP/NT-proBNP and troponin T/I quartiles differed significantly (p<0.001). Stepwise risk stratification was achieved by combining NT-proBNP/BNP and troponin T/I. From Cox proportional hazards model, age, modified body mass index, mutation (Val30Met vs. Non-Val30Met) and BNP/NT-proBNP (Q1-Q3 pooled vs. Q4) were identified as independent predictors of survival in patients with mutant-type ATTR. Conclusions In this ATTR patient cohort, cardiac biomarkers were abnormal in a substantial percentage of patients irrespective of genotype. Along with age, mBMI, and mutation (Val30Met vs. Non-Val30Met), cardiac biomarkers were associated with surrogates of disease severity with BNP/NT-proBNP identified as an independent predictor of survival in ATTR